Keg Carbination confusion!

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
Carbination trouble!

Ok. This one has got me super confused. I have been kegging now for a solid 7-8 years. My go to method is 30psi for 36 hours. It has worked flawlessly. Well this last batch things are not same. My good brewing friend Chris made an amazing Mexican Lager and we split the batch so we each had our own keg. We soaked lime zest (Chris did lime peel) in tequila for a few days, then strained out the zest/peel and added the tequila to the keg (about 12-16 oz). Ok, so with that said I went with my method of 30psi for 36 hrs. After 36 hours beer was still flat. I then put it on serving pressure (8-10 psi) for about 4 days and still flat. Fearing over carbination I went with 20 psi for 12 hours, still flat. Getting a bit frustrated I then went 30 psi again for 18-20 hours.....still flat!

So whats the deal? I have never added hard liquor to a brew, so is that the issue? The tequila? Chris' brew carbed up great. The only difference we had was the yeast and he did peel vs zest of the lime.

My next step is to do the rock and roll method for fast/forced carbination. Anyone do that consistently?

Any and all thought or comments are appreciated greatly. Cheers!
 

day_trippr

Structural Duct Tape Sales Engineer
Joined
May 31, 2011
Messages
38,659
Reaction score
21,856
Location
Stow, MA
My guess is the keg is leaking gas.

My next step is to do the rock and roll method for fast/forced carbination. Anyone do that consistently?

I have a few times done the "rock and roll" - at chart pressure - to carb up a full keg in an afternoon with no risk of over-carbonation...

Cheers!
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
HBT Supporter
Joined
May 14, 2014
Messages
13,412
Reaction score
10,283
Location
Renton
Any chance your keg is filled above the cylindrical wall cross section, so that the surface area exposed to the CO2 is significantly reduced? Carbonation rate is dependent on the area into which the CO2 is diffusing.

I don't think a leak is the issue, as a leak won't affect the pressure in the headspace, unless the leak rate is very high, and if that is the case, your CO2 tank will be empty in short order.

Brew on :mug:
 

FloppyKnockers

Well-Known Member
Joined
Nov 11, 2014
Messages
2,217
Reaction score
2,115
Location
Fort Worth
I used liqueur as a priming sugar with good result and no carb issue. If I had to guess, I would say something was in your keg that might be stifling the carbo process. I say rock n rock with it. If you over carb, you can always decarb. (I rock n roll regularly)

My method:
Keg at serving temp
Hook up CO2 at ~27-30 psi
Lay keg on side with gas post up
Rock back and forth to the rhythm of a washing machine
Do this for 2m 5sec
Hook up to serving pressure and depressurize excess pressure
It should be slightly under-carbed, but bubbly at this point

Let us know.
 
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
May seem too obvious but, it the gas turned on going to the keg? I have forgotten to do this once or twice.

Are you getting and "hissing" from the pressure valve when releasing?
I thought the same thing! Ya its all turned on. Definitely full of pressure when I release it.
 
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
I used liqueur as a priming sugar with good result and no carb issue. If I had to guess, I would say something was in your keg that might be stifling the carbo process. I say rock n rock with it. If you over carb, you can always decarb. (I rock n roll regularly)

My method:
Keg at serving temp
Hook up CO2 at ~27-30 psi
Lay keg on side with gas post up
Rock back and forth to the rhythm of a washing machine
Do this for 2m 5sec
Hook up to serving pressure and depressurize excess pressure
It should be slightly under-carbed, but bubbly at this point

Let us know.
Great. Thank you. Do you release the pressure after rocking it right away, or wait a little while?
 
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
Any chance your keg is filled above the cylindrical wall cross section, so that the surface area exposed to the CO2 is significantly reduced? Carbonation rate is dependent on the area into which the CO2 is diffusing.

I don't think a leak is the issue, as a leak won't affect the pressure in the headspace, unless the leak rate is very high, and if that is the case, your CO2 tank will be empty in short order.

Brew on :mug:
It's filled up just below the gas dip tube.
 
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
My guess is the keg is leaking gas.



I have a few times done the "rock and roll" - at chart pressure - to carb up a full keg in an afternoon with no risk of over-carbonation...

Cheers!
Thank you for the reply. Appreciate it. Rock and roll is my next step.
 

FloppyKnockers

Well-Known Member
Joined
Nov 11, 2014
Messages
2,217
Reaction score
2,115
Location
Fort Worth
Great. Thank you. Do you release the pressure after rocking it right away, or wait a little while?
Pretty much right away. No urgency. Just as soon as I right the keg and I'm ready to put it back in the kegerator. Carful about some spray though. Release the pressure slowly.
 

bracconiere

Jolly Alcoholic
HBT Supporter
Joined
Jan 19, 2018
Messages
23,924
Reaction score
14,053
Location
S.AZ
you say when you pull the PRV on the keg it vents? how many kegs, and do they go through a manifold with check valves?

(just racking my brain trying to figure it...another thought i just had, did you swap recently? it IS co2 right?)


edit: if there was a mistake and it's a scuba tank, the psi would be 3000psi not 750-1000 on the HP guage...not sure if that would be possible, but a thought...
 
Last edited:

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
HBT Supporter
Joined
May 14, 2014
Messages
13,412
Reaction score
10,283
Location
Renton
Great. Thank you. Do you release the pressure after rocking it right away, or wait a little while?
When doing "rock and roll" at chart (equilibrium) pressure, you don't vent - that would just waste CO2. The process is to rock and roll until you don't hear CO2 flowing, and then wait about 15 minutes. Repeat until you no longer hear CO2 flowing. Then extend wait intervals to about 1 hr, and repeat until no CO2 flow heard.

If you do rock and roll at pressures above chart pressure (the fastest way to over-carb a keg) then you want to vent at the end of the process, and re-pressurize to chart pressure. You can test carbonation at various intervals during the rock and rolling to see when the carb level is about where you want it (a picnic tap is useful here, and good to rest about 15 minutes before taking a sample pour.)

It is possible to do the rock and roll with over-pressure in a quantitative way, if you have a scale with a capacity of 25 kg (55 lb) and resolution of 1 gram. You have to start right after kegging, as you need to know what the starting level of carbonation is - about 0.8 volumes after an ale fermentation in the mid 60's, and about 1.1 volumes after a lager fermentation at about 50. You then figure out how many volumes you have to add to reach your target carbonation level.

Let's say you did an ale, and you want to carbonate to 2.5 volumes. You're starting with 0.8 volumes, so you need to add 2.5 - 0.8 = 1.7 volumes. 1 volume of carbonation is equal to 2 g/L of dissolved CO2, and 5 gal is equal to 19 L, so to add 1.7 volumes to 5 gal we need to add 1.7 * 2 * 19 = 65 g of CO2 to the keg.

The process is this (keg should be chilled first):
  1. Attach the CO2 line to the keg and weigh it using a gram scale. Write down the weight in g, and add 65 g.
  2. Turn on the gas and rock and roll for a while.
  3. Reweigh the keg
  4. lf less than the final weight calculated in 1, repeat starting at step 2.
  5. Your carbonation is complete, reduce pressure to chart pressure.
Gotta give credit to @bracconiere for the idea of monitoring weight while burst carbing. He's the first one I know of that talked about this on HBT.

Brew on :mug:
 
Last edited:
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
When doing "rock and roll" at chart (equilibrium) pressure, you don't vent - that would just waste CO2. The process is to rock and roll until you don't hear CO2 flowing, and then wait about 15 minutes. Repeat until you no longer hear CO2 flowing. Then extend wait intervals to about 1 hr, and repeat until no CO2 flow heard.

If you do rock and roll at pressures above chart pressure (the fastest way to over-carb a keg) then you want to vent at the end of the process, and re-pressurize to chart pressure. You can test carbonation at various intervals during the rock and rolling to see when the carb level is about where you want it (a picnic tap is useful here, and good to rest about 15 minutes before taking a sample pour.)

It is possible to do the rock and roll with over-pressure in a quantitative way, if you have a scale with a capacity of 25 kg (55 lb) and resolution of 1 gram. You have to start right after kegging, as you need to know what the starting level of carbonation is - about 0.8 volumes after an ale fermentation in the mid 60's, and about 1.1 volumes after a lager fermentation at about 50. You then figure out how many volumes you have to add to reach your target carbonation level.

Let's say you did an ale, and you want to carbonate to 2.5 volumes. You're starting with 0.8 volumes, so you need to add 2.5 - 0.8 = 1.7 volumes. 1 volume of carbonation is equal to 2 g/L of dissolved CO2, and 5 gal is equal to 19 L, so to add 1.7 volumes to 5 gal we need to add 1.7 * 2 * 19 = 65 g of CO2 to the keg.

The process is this (keg should be chilled first):
  1. Attach the CO2 line to the keg and weigh it using a gram scale. Write down the weight in g, and add 65 g.
  2. Turn on the gas and rock and roll for a while.
  3. Reweigh the keg
  4. lf less than the final weight calculated in 1, repeat starting at step 2.
  5. Your carbonation is complete, reduce pressure to chart pressure.
Gotta give credit to @bracconiere for the idea of monitoring weight while burst carbing. He's the first one I know of that talked about this on HBT.

Brew on :mug:
Great info. Thank you!
 
OP
OP
storytyme

storytyme

Well-Known Member
Joined
Jun 28, 2012
Messages
388
Reaction score
62
you say when you pull the PRV on the keg it vents? how many kegs, and do they go through a manifold with check valves?

(just racking my brain trying to figure it...another thought i just had, did you swap recently? it IS co2 right?)


edit: if there was a mistake and it's a scuba tank, the psi would be 3000psi not 750-1000 on the HP guage...not sure if that would be possible, but a thought...
It goes through a manifold. 8 kegs. I don't have a PRV on the keg. I just press the gas post to release pressure. I did check and it is CO2.
 
Top